The Field Core will be responsible for the identification and recruitment of subjects for the three studies in this PGRC renewal application, for the collection of baseline and follow-up data for specific studies, for the abstraction of information from the subject's medical record, and for the acquisition of blood specimens required for 0001 and 0002. Five Continuing Care Retirement Communities (CCRC) with long established affiliations with the PGRC, and the Opportunities Towers, a low income housing project that is presently the site of a recruitment pilot for the PGRC, constitute the primary study sites. Approximately 1000 currently active members of the PGRC Database Registry who reside in these facilities are available for enrollment into the studies. An additional 2400 residents will be approached to participate in one of the three studies during a three stage recruitment process. A screening interview designed to provide information to determine eligibility for each of the studies will be administered. It includes scales to assess cognitive function, depressive symptomatology, physical function, health conditions, use of health services and sleep disturbance. In most instances previously used and validated scales will be used. In contrast to previous grant periods, the Database will contain only individuals who are actively enrolled in one of the proposed studies; this change is planned to increase the economic efficiency of the Field Core. Individuals recruited to the Core will continue to be a resource for additional studies undertaken by PGRC investigators or other researchers at the PGRC institutions. The Field Core will be under the overall direction of Dr. Jana Mossey who has been responsible for the PGRC Cores during the current grant period. An experienced Nurse researcher will assume responsibility for the day to day operations of the Field Core.